1. Field of the Invention
This invention relates to a method of rewriting information recorded on a record medium, and more particularly to a method for rewriting information recorded on an information record medium of write-once record type such as an optical memory card or an optical disk.
2. Description of the Related Art
In case where correction or rewriting of information is required after the information has been recorded on a write-once type record medium such as an optical card or an and optical disk, the old information is rewritten by recording new corrected or revised information. When all the corrected information is newly recorded, a portion of the information which is not changed at all is recorded on the record medium in a duplicate manner, so that a data record area on the record medium is wasted and could not be utilized optimally. Such a problem is not serious when an amount of the data recorded on the record medium is small. However, when a large amount of data such as image data is used, a considerably large data record area is wasted for rewriting the information.
In case of using a rewritable type record medium, the old information can be erased and the new information is recorded thereon, so that the data record area is not wasted at all. However, when a speed of recording the information on the record medium is relatively low, a relatively long time period is necessary for rewriting the information and the efficiency of the data processing becomes low.